1. Field of the Invention
The present invention relates to apparatus for cleaning fan blades including those of air conditioning and ventilating fans. More particularly, the present invention relates to a pocket-sized apparatus for removing residue built up on the blades of multi-blade wheels of centrifugal fan units typically found in central air conditioning and ventilating fans.
2. General Background
Air conditioning and ventilating units including residential, commercial and industrial units, typically use centrifugal fans which consist of a wheel with blades at its rim, the whole rotating within a housing. The blades are typically forward-curved blades which have the tip inclined in the direction of fan rotation for compactness for a given air delivery and static pressure and for operating at lower tip speed and thus apt to be quieter. In operation, however, a residue of lubricating oils, dust and other particulate matter will inevitably build up on the concave or inside surface of the blades thereby reducing the efficiency of the unit, often by 50% or more. To maintain efficiency therefore, it is necessary to regularly service the fan and particularly to remove the residue built up.
Various devices and methods are well known for cleaning fan blades, such devices include wire brushes, compressed air and highly pressurized water.
Many of these devices suffer in that they require bulky and heavy equipment such as hoses and compressor units or a readily available water supply. Further, devices such as brushes are not designed to fit snugly between fan blades and therefore do not effectuate a thorough cleaning of the blade surfaces.